Don't Push - S6-E2
Continuity mistake: While trying to take a new Family Portrait, after Cameron, Mitchell, and Lily shake out their faces, say cheese and take another photo, Cameron goes to look at the laptop screen and there's a closeup of that newest photo, but when he tells Mitchell to look at the screen it's a different photo - note Lily's goofy eyes, etc.
Continuity mistake: Pepper states in this episode that he doesn't have any kids, but in 4-14 "A Slight at the Opera" he talks about a son he has who is a Navy Seal.
Continuity mistake: Whilst Clare and her new 'best friend' are talking to the flight attendant, the two glasses change from empty to full in the next shot.
Continuity mistake: When Alex opens the door for Sanjay she is wearing red headphones around her neck, in the shot after that the headphones are gone. Two shots later, they reapear. (00:11:10)
Answer: He has seen himself dancing, and is mortified at how bad he looks.